The present invention relates to the discovery that a group of 1,1,2-triphenylbut-1-ene derivatives are useful for inhibiting endometriosis and uterine fibroid disease in women.
Unterine fibroid disease (uterine fibrosis) is an old and ever present clinical problem which goes under a variety of names, including uterine hypertrophy, uterine lieomyomata, myometrial hypertrophy, fibrosis uteri, and fibrotic metritis. Essentially, uterine fibroid disease is a condition where there is an inappropriate deposition of fibroid tissue on the wall of the uterus.
This condition is a cause of dysmenorrhea and infertility in women. The exact cause of this condition is poorly understood but evidence suggests that it is an inappropriate response of fibroid tissue to estrogen. Such a condition has been produced in rabbits by daily administrations of estrogen for 3 months. In guinea pigs, the condition has been produced by daily administration of estrogen for four months. Further, in rats, estrogen causes similar hypertrophy.
The most common treatment of uterine fibroid disease involves surgical procedures which are both costly and sometimes a source of complications such as the formation of abdominal adhesions and infections. In some patients, initial surgery is only a temporary treatment and the fibroids regrow. In those cases, a hysterectomy is performed which effectively ends the fibroids, but also the reproductive life of the patient. Also, gonadotropin releasing hormone antagonists may be administered, but their use is tempered by the fact they can lead to osteoporosis.
Endometriosis is a condition of severe dysmenorrhea, which is accompanied by severe pain, bleeding into the endometrial masses or peritoneal cavity, and often leads to infertility. The cause of the symptoms of this condition appear to be ectopic endometrial growths which respond inappropriately to normal hormonal control and are located in inappropriate tissues. Because of the inappropriate locations for endometrial growth, the tissue seems to initiate local inflammatory-like responses causing macrophage infiltration and a cascade of events leading to initiation of the painful response. The exact etiology of this disease is not well understood and its treatment by hormonal therapy is diverse, poorly defined, and marked by numerous unwanted and perhaps dangerous side effects.
One of the treatments for this disease is the use of low dose estrogen to suppress endometrial growth through a negative feedback effect on central gonadotropin release, and subsequent ovarian production of estrogen. However, it is sometimes necessary to use continuous estrogen to control the symptoms. This use of estrogen can often lead to undesirable side effects and even the risk of endometrial cancer.
Another treatment consists of continuous administration of progestin which induces amenorrhea and, by suppressing ovarian estrogen production, can cause regressions of the endometrial growths. The use of chronic progestin therapy is often accompanied by the unpleasant central nervous system side effects of progestin, and often leads to infertility due to suppression of ovarian function.
A third treatment consists of the administration of weak androgens, which are effective in controlling the endometriosis. However, they induce severe masculinizing effects. Several of these treatments have also been implicated in causing a mild degree of bone loss with continued therapy.
Therefore, new methods of treating endometriosis are desirable.